Cold weather low flow miniature spray nozzle assembly and method

ABSTRACT

A low flow compact spray head design for cleaning applications, especially for camera lens wash includes a miniature spray nozzle head which is about 5 mm in diameter or less for a single direction spray nozzle and about 8 mm in diameter of less for a nozzle with multiple sprays. The washer fluid is fed from the bottom of nozzle along a flow axis and is separated into two flows via two power nozzles or inlets which turn the flows 90° to become opposing jets impinging upon each other inside an interaction region. Uniform stream lines are generated by the two direct facing jets and converge at the nozzle throat to become a uniform spray fan, which is on a plane perpendicular to the axis of cylindrical nozzle head. This fluidic circuit design enables a miniature size low flowrate nozzle to operate well consistently with low flow rate (e.g., a flow rate of about 150 mL/min to about 300 mL/min at 25 psi, or even a flow rate of about 250 mL/min at 25 psi or above, at a viscosity of about 25 CP) at cold temperate (−4° F. or lower) with 50 percent ethanol. This nozzle design is capable of generating two or more different oriented spray fans (e.g., fans spraying in opposing directions) from one single nozzle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and benefit of U.S. ProvisionalApplication No. 62/620,826 entitled “COLD WEATHER LOW FLOW MINIATURESPRAY NOZZLE ASSEMBLY AND METHOD,” filed on Jan. 23, 2018, which ishereby incorporated by reference in its entirety. This application isalso a continuation-in-part of U.S. Utility application Ser. No.15/759,242 entitled LOW-FLOW MINIATURE FLUIDIC SPRAY NOZZLE ASSEMBLY ANDMETHOD,” filed on Mar. 12, 2018 which is a national phase entryapplication of International Application No. PCT/US2017/62044 filed onNov. 16, 2017 which claims priority to U.S. Provisional Application No.62/423,016 filed on Nov. 16, 2016.

This application is also related to the following commonly owned patentapplications: PCT application number PCT/US16/57762 entitled“Micro-sized Structure and Construction Method for Fluidic OscillatorWash Nozzle” (now WIPO Publication WO 2017/070246), PCT applicationnumber PCT/US15/45429, entitled “Compact Split-lip Shear Washer Nozzle”,(now WIPO Publication WO 2016/025930), and U.S. application Ser. No.15/303,329, entitled “Integrated automotive system, compact, low profilenozzle assembly, compact fluidic circuit and remote control method forcleaning wide-angle image sensor's exterior surface”, (now US PublishedApplication US2017/0036650), the entire disclosures of which areincorporated herein by reference.

FIELD OF THE DISCLOSURE

The present disclosure relates to very small or compact spray nozzleassemblies, and particularly for miniaturized automotive washer nozzlesfor cleaning external surfaces such as external camera lens surfaces.

BACKGROUND

Fluidic type washer nozzles are well known for high efficiency (bigcoverage, high speed with low flow rate) spray performance. However, themajor limitation of fluidic nozzle is that the package size needs to belarge enough (for example, from feed to exit need to be at least 6 mmfor most of fluidic circuits).

For some applications, package size is a big concern due to very limitedavailable space. Jet spray nozzles were commonly used in suchapplications. Because of narrow spray pattern, jet spray nozzles needhigher flow rate or longer duration time to clean up a glass or externallens surface. Jet nozzles spray nozzles have smaller package size thanfluidic nozzles, but do not have effective spray patterns.

Some shear nozzles can be made to generate useful sprays for washing andcan be made adjustable with ball insert in nozzle housing, but sizeconstraints have remained a problem. Automotive designers want verycompact nozzle assemblies for automotive washer nozzles, but also wantan even spray distribution. Automotive OEMs also want a nozzle which isvery economical and versatile. For example, exterior trim assembliesoften combine many functions, such as the CHMSL light assemblies, whichcan include other features such as external cameras, but cleaning thelenses on those cameras becomes problematic, if the designer's visionfor exterior trim is to be preserved.

Shear nozzles are sometimes used for small package-size applications,and they perform well for geometries where a spray fan is aligned withthe axis of the feed hole, but poorly for geometries where the spray fanperpendicular to the axis of the feed hole. Other challenges includespray aim & tooling complications which become major constraints forproposed designs including shear nozzles, and so is washer sprayperformance when spraying cold, high viscosity fluids. FIGS. 1A through1G illustrate prior art in the area of vehicle window wash and camerawash systems and one of applicant's prior compact washer nozzle members100 (from the references incorporated above).

Cold weather spray performance is another difficult objective, butsolving cold weather washing spray generation problems in a miniaturizednozzle assembly is an extremely desirable objective, especially forvehicle camera wash nozzle applications. Under cold temperatureconditions, good spray coverage on the vehicle camera lens is veryimportant to remove dirt, ice or salt stains from camera lens or similarsensor surfaces.

Thus, there is a need for a practical, economical, readily manufacturedand very compact automotive camera lens washer nozzle configuration andcleaning method.

SUMMARY

Accordingly, it is one object of the present disclosure to overcome theabove mentioned difficulties by providing a new way to integrate thedesirable cold weather, low flow, high viscosity spray orientationfeatures with a very compact (e.g., 5 mm diameter) nozzle assembly sprayhead.

In accordance with the present disclosure, a new small (e.g., 5 mmdiameter) shear nozzle is optimized to provide the desired sprays from asmall spray head profile. The shear nozzle geometry of the presentdisclosure generates uniform spray fan perpendicular to the axis of feedhole at a low washer fluid flow rate, while providing excellent coldperformance, and easy manufacturability. Moreover, this nozzle design iscapable of spraying two differently oriented fans from one singlenozzle.

A low flow compact spray head design for cleaning applications isespecially well suited for auto camera lens wash applications andincludes a miniature spray nozzle head which is about 5 mm in diameteror less for a single direction spray nozzle and about 8 mm in diameterof less for a nozzle with multiple sprays. The washer fluid is fed fromthe bottom of nozzle housing along a vertical interior lumen's flowaxis, then the pressurized fluid separates into two flows. Those twoflows are fed into two power nozzle inlets which make the flows turn90°, become two jets facing each other inside an interaction region.Uniform stream lines are generated by the two direct facing jets andconverge at the nozzle throat to become a uniform spray fan, which is ona plane perpendicular to the axis of cylindrical nozzle head. Thisfluidic circuit design enables a miniature size low flowrate nozzle tooperate consistently with low flow rate (e.g., a flow rate of about 150mL/min to about 300 mL/min at 25 psi, or even a flow rate of about 250mL/min at 25 psi or above, at a viscosity of about 25 CP) at varioustemperatures including cold temperatures (i.e., about −4° F. or lower)with 50 percent ethanol. This nozzle design is capable of generating twoor more different oriented spray fans (e.g., fans spraying in opposingdirections) from one single nozzle.

The nozzle assembly method of the present disclosure provides a new wayto assemble a 5 mm diameter spray nozzle with variable spray fan in atwo-piece nozzle assembly. The spray fan angle may be selected to be inthe range of about 15° to about 70°. Spray aim angles may be selected tobe in the range of about −15° to about +15°. The system operates wellwith washer fluid flow rates of around about 200 mL/min to about 600mL/min at 25 psi. The nozzle assembly and method of the presentdisclosure provide a lens washer system capable of operating effectivelywith a low flow rate (e.g., a flow rate of about 150 mL/min to about 300mL/min at 25 psi, or even a flow rate of about 250 mL/min at 25 psi orabove, at a viscosity of about 25 CP) and the spray nozzle performs verywell with high viscosity washer fluid (e.g., 50 percent ethanol) atvarious temperatures including cold temperatures (i.e., about −4° F. orlower).

The nozzle assembly and method of the present disclosure includes atwo-piece spray nozzle assembly where both housing and insert membersare economically manufacturable for high volume robust production. Thenozzle assembly and method of the present disclosure may be implementedwith a one nozzle spray or with two or more variously oriented sprayfans. In a multi-spray embodiment, one nozzle assembly is configurableto generate two separate spray fans aimed along diverging or opposingspray axes to clean separate and differently oriented (e.g., cameralens) surfaces.

The above and still further objects, features and advantages of thepresent disclosure will become apparent upon consideration of thefollowing detailed description of a specific embodiment thereof,particularly when taken in conjunction with the accompanying drawings,wherein like reference numerals in the various figures are utilized todesignate like components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B illustrate a vehicle with a back-up camera system asdisclosed in U.S. Pat. No. 7,965,336;

FIG. 1C is a schematic diagram illustrating an automotive imaging systemwith a nozzle assembly configured for cleaning the imaging system'sexterior objective lens surface, in accordance with prior work;

FIGS. 1D through 1G illustrate a compact split-lip shear washer nozzlefor use in automotive applications in accordance with the Prior Art;

FIG. 2A illustrates a spray nozzle according to one embodiment of thepresent disclosure and a cross-sectional side view through line A-A ofFIG. 2A;

FIG. 2B illustrates a cross-sectional top view through line B-B of FIG.2A illustrating an interaction region of a spray nozzle and an insertmember separate from a housing according to one embodiment of thepresent disclosure;

FIG. 3A illustrates an enlarged top cross sectional view through lineBOB of FIG. 2A according to an embodiment of the present disclosure;

FIG. 3B illustrates an enlarged cross sectional view through line A-A ofFIG. 2A according to an embodiment of the present disclosure;

FIG. 4A is a photograph illustrating a top view of a spray nozzleaccording to one embodiment of the present disclosure operating at roomtemperature and with a nozzle flow rate of about 250 ml/min at 25 psi;

FIG. 4B is a photograph illustrating a side view of a spray nozzleaccording to one embodiment of the present disclosure operating at roomtemperature and with a nozzle flow rate of about 250 ml/min at 25 psi;

FIG. 4C is a photograph illustrating a top view of a spray nozzleaccording to one embodiment of the present disclosure operating at about−4 degrees F. with a nozzle flow rate of about 250 ml/min at 25 psi anda 50% ethanol fluid spray;

FIG. 5A is a perspective view of a spray nozzle according to anotherembodiment of the present disclosure where the nozzle of FIG. 5A has theability to yield two or more spray fans;

FIG. 5B illustrates a front view of the nozzle assembly of FIG. 5A;

FIG. 5C illustrates a rear view of the nozzle assembly of FIG. 5A;

FIG. 6A is a perspective cross sectional view of an insert for the spraynozzle according to another embodiment of the present disclosure;

FIG. 6B is an opposite cross sectional view of an insert for the spraynozzle according to another embodiment of the present disclosure;

FIG. 6C is a top perspective view of the insert for the spray nozzle;

FIG. 7 is a cross sectional view of an embodiment of the spray nozzleaccording to the present disclosure;

FIG. 8A illustrates a multi-spray nozzle assembly according to oneembodiment of the present disclosure in operation;

FIG. 8B illustrates a multi-spray nozzle assembly according to oneembodiment of the present disclosure in operation;

FIG. 8C illustrates a multi-spray nozzle assembly according to oneembodiment of the present disclosure in operation; and

FIG. 9 is a perspective view of a nozzle assembly according to anembodiment of the present disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

Reference will now be made in detail to exemplary embodiments of thepresent disclosure, examples of which are illustrated in theaccompanying drawings. It is to be understood that other embodiments maybe utilized and structural and functional changes may be made withoutdeparting from the respective scope of the present disclosure. Moreover,features of the various embodiments may be combined or altered withoutdeparting from the scope of the present disclosure. As such, thefollowing description is presented by way of illustration only andshould not limit in any way the various alternatives and modificationsthat may be made to the illustrated embodiments and still be within thespirit and scope of the present disclosure.

As used herein, the words “example” and “exemplary” mean an instance, orillustration. The words “example” or “exemplary” do not indicate a keyor preferred aspect or embodiment. The word “or” is intended to beinclusive rather an exclusive, unless context suggests otherwise. As anexample, the phrase “A employs B or C,” includes any inclusivepermutation (e.g., employs B; A employs C; or A employs both B and C).As another matter, the articles “a” and “an” are generally intended tomean “one or more” unless context suggest otherwise.

Similar reference numerals are used throughout the figures. Therefore,in certain views, only selected elements are indicated even though thefeatures of the assembly are identical in all of the figures. In thesame manner, while a particular aspect of the disclosure is illustratedin these figures, other aspects and arrangements are possible, as willbe explained below. Turning now to a detailed description of the nozzleassembly and compact spray nozzle member of the present disclosure theattached Figures (FIGS. 2A through 10) illustrate the various specificembodiments of the present disclosure.

In one instance, specific illustrative embodiments for the spray nozzlesystem and method of the present disclosure, in which a very compactnozzle assembly 200 is illustrated where such a system generates one ormore aimed spray fans or patterns. The miniaturized (e.g., 5 mmdiameter) shear nozzle assembly 200 of the present disclosure isoptimized to provide the desired sprays from a small spray head profile.In one embodiment, the spray head of the present disclosure is anysuitable height including, in one non-limiting embodiment, about 5 mmtall or less including about 4.6 mm tall or about 3 mm tall. The shearnozzle geometry of the present disclosure generates uniform spray fan(see FIGS. 4A-4C) along a spray axis in a spray fan plane which isperpendicular to the central lumen axis of the fluid inlet or feed hole(see FIGS. 3A through 3C), at a low washer fluid flow rate, whileproviding excellent cold performance, and easy manufacturability. In analternative embodiment, as is illustrated in FIGS. 5A through 8C, anozzle design according to another embodiment of the present disclosureis disclosed as configurable as a multi-spray nozzle assembly 300capable of spraying two different oriented fans from one single nozzle.A low flow compact spray head design for cleaning applications,especially for camera lens wash comprises a miniature spay nozzle head200 which is, in one embodiment, about 5 mm in diameter or less. Washerfluid (or some other fluid, liquid, or even air) is fed from the bottomof nozzle 200 along a nozzle assembly lumen central flow axis 202, andthen the fluid is separated into two flows 204 a and 204 b. Flows 204 aand 204 b are then fed into a first power nozzle 220 a and a secondpower nozzle 220 b, where the power nozzles or inlets 220 a and 220 bdefine lumens or channels of fluid communication which make the flowsturn 90°, thereby generating two jets which oppose or face each otherwhere the flows collide or impinge upon one another inside aninteraction region 230. As best seen in the two views of FIGS. 3A and3B, uniform stream lines are generated by the two impinging or directfacing jets and converge at the nozzle throat or outlet orifice 240 tobecome a uniform spray fan 208, which is projected along a central sprayaxis on a plane perpendicular to the inlet lumen's central flow axis ofcylindrical nozzle head. The shear nozzle assembly of claim 1, whereinthe position of the power nozzles relative to the interaction regionincludes a top clearance dimension and a bottom clearance dimensionwherein the top clearance dimension is greater than the bottom clearancedimension. The transverse throat of the insert member is definedpartially by a first sidewall 210A, a second sidewall 210B, a floorsurface 212B and a roof surface 212A. The first sidewall and secondsidewall are opposite one another and are substantially planar and thefloor surface and roof surface may be opposite one another and besubstantially planar. The nozzle housing may include a dome-shaped tipwith a diameter size of approximately 5.6 mm.

This fluidic circuit design enables miniature size low flowrate nozzle200 to operate consistently with a low flow rate (e.g., a flow rate ofabout 150 mL/min to about 300 mL/min at 25 psi, or even a flow rate ofabout 250 mL/min at 25 psi or above, at a viscosity of about 1-25 CP) atvarious temperatures including cold temperatures (i.e., about −4° F. orlower) with a liquid or aqueous system including up to about 50 percentethanol. The configuration of nozzle assembly 200 can be altered toprovide a two spray embodiment (see, e.g., nozzle assembly 300) whichoperates on the same principals and is capable of generating two or moredifferently oriented spray fans (e.g., fans spraying in opposingdirections) from one single nozzle assembly (see nozzle 300 asillustrated in FIGS. 5A through 8C).

The nozzle assembly method of the present disclosure provides a novelway to assemble a miniaturized (e.g., about 5 mm diameter) spray nozzlewith variable spray fan in a two-piece nozzle assembly. The spray fanangle may be selected to be in the range of about 15° to about 70°.Spray aim angles may be selected to be in the range of about −15° toabout +15°. In one embodiment, the system of the present disclosureoperates well with washer fluid flow rates of around about 200 mL/min toabout 600 mL/min at 25 psi. The nozzle assembly and method of thepresent disclosure provide a lens washer system capable of operatingeffectively with a low flow rate (e.g., a flow rate of about 150 mL/minto about 300 mL/min at 25 psi, or even a flow rate of about 250 mL/minat 25 psi or above, at a viscosity of about 25 CP) and the spray nozzleperforms very well with high viscosity washer fluids (e.g., fluidscontaining up to about 50 percent ethanol) under cold temperatures(e.g., about −4° F. or lower).

The nozzle assembly and method of the present disclosure includes atwo-piece spray nozzle assembly 200 where both housing member 206 andinsert member 216 (see FIG. 2A) are economically manufacturable (e.g.,by molding from plastic materials, by 3D printing, by injection molding,etc.) for high volume robust production. The nozzle assembly and methodof the present disclosure may be implemented with a one nozzle spray orwith two or more variously oriented spray fans. As shown in FIGS. 8Athrough 8C, nozzle assembly 300 is configurable to generate first andsecond separate spray fans aimed along diverging or opposing spray axesto clean first and second separate and differently oriented camera lenssurfaces.

Returning to FIGS. 3A and 3B, in operation, two flows from first andsecond inlets or power nozzles 220 a and 220 b enter interaction region230 from opposite directions, and the impinging or colliding flowsproduce shear shape stream lines flowing distally along the interactionregion's central spray axis toward exit orifice or throat 240 to form aflat fan spray 208 (as is illustrated in FIGS. 4A through 4C). The exitside throat 240, best seen in FIG. 3A, forms the desired spray fan shapeand reduces failure of such a small nozzle while operating in coldambient conditions. The spray would be a jet without the fluidic effectsgenerated via operation of exit side throat 240. In one embodiment,nozzle assembly 200 of the present disclosure is capable of reliablygenerating a satisfactory spray fan when fan inlet supply fluid issupplied at a low flow rate (e.g., a flow rate of about 150 mL/min toabout 300 mL/min at 25 psi, or even a flow rate of about 250 mL/min at25 psi or above, at a viscosity of up to about 25 CP). Additionally,spray nozzle 200 performs very well even under cold temperatures ofabout −4° F. or lower (see, e.g., FIG. 3) with a fluid/aqueous liquidhaving a high viscosity (e.g., a washer fluid comprising about 50percent ethanol and about 50 percent water).

Another advantage of the nozzle and method of the present disclosure isthat the insert member (e.g., 216) is injection-mold friendly or even 3Dprinting friendly, robust for manufacturing, assembling, retention andsealing. For each power nozzle 220 a and/or 220 b the lumen crosssectional area or inlet size is, in one non-limiting instance, about 1mm by about 0.4 mm. In this instance, the typical interaction regionwidth is in the range of about 0.4 mm to about 0.6 mm. The exit throator outlet orifice 240 (as illustrated from the side in FIGS. 2B and 3B)is axially aligned with and sprays through a side aperture 242 inhousing member 206.

In one embodiment, typical exit throat size is around about 0.5 mm byabout 1 mm. The power nozzle lumen area or inlet size is big compared tothe exit throat in order to reduce restrictions and turbulence in (e.g.,comfort) the flows fed from the bottom opening or housing inlet orifice.In order to balance the upward vector of feed flow inside theinteraction region 230 (as best seen in the two views of FIG. 2B), topclearance (denote d by Δ1) is greater than bottom clearance (denoted byΔ2). This inlet feed condition assists to maintain a stable spray.

In one embodiment, the spray fan is adjustable for different washingapplications by adjusting the ratio of the exit throat area 240 and exitside throat 242. The distance between the inlet and exit throat alsoaffects the spray fan. Spray aim angle may also be changed by making anoffset between the exit side throat 242 and the exit throat with anadded a down draft angle to the exit top or bottom surface (see, e.g.,FIG. 7). Spray thickness will increase when the exit throat is divergedby drafted top/bottom exit surface (see, e.g., FIG. 7).

As illustrated in FIGS. 5A through 8C, these Figures show a multi-spraynozzle assembly 300 with housing 306 and insert 316, the circuit designof the present disclosure can make one single nozzle assembly which aimsand generates two or more separate spray fans with diverging or opposingspray axes to wash lenses or other surfaces having differingorientations. In this embodiment, there are no power nozzles but aninterior lumen 320 that extends within the insert 316. The interiorlumen 320 allows fluid to flow therethrough and split along centermember 330 into a first entry lumen 322A and a second entry lumen 322Bin direct communication with interaction region 340. Notably the area ofthe first and second entry lumens 322A, 322B are larger than theinteraction region 340. First outlet 350 and second outlet 360 extendopposite one another from the interaction region 340 and are configuredto align with first exit outlet 352 and second exit outlet 362 asillustrated by FIG. 7.

For the exemplary embodiment illustrated in FIGS. 8A through 8C, thespray orientation of a first spray from first outlet 350 and first exitoutlet 352 is: aim=0°, roll 0°, while the spray orientation of a secondspray from second outlet 360 and second exit outlet 362 is: aim=−10°,roll=10°. The 10° roll angle is achieved by rolling the interactionregion's cross sectional slot-shaped lumen along the second outlet 360(see FIGS. 6A, 6B, 6C). The −10° aim angle is achieved by offset of thesecond outlet 360 and second exit outlet 362 in the housing 306 and adown draft at bottom exit floor 370. Both housing 206, 306 and insert216, 316 designs are molding friendly. The separation angle or the anglebetween the first and second spray axes of the nozzle shown in FIGS. 5Athrough 8C (between two spray fans) is 180°. This separation angle couldbe about 30°, about 45°, about 90° or even any other angle depending onthe package size of the nozzle. Applicant's development work on thenozzle assembly of the present disclosure (e.g., 200, 300) indicatesthat the nozzles of the present disclosure also work with oil, air orother fluids.

Although the embodiments of the present disclosure have been illustratedin the accompanying drawings and described in the foregoing detaileddescription, it is to be understood that the present disclosure is notto be limited to just the embodiments disclosed, but that the presentdisclosure described herein is capable of numerous rearrangements,modifications and substitutions without departing from the scope of theclaims hereafter. The claims as follows are intended to include allmodifications and alterations insofar as they come within the scope ofthe claims or the equivalent thereof.

Accordingly, the present specification is intended to embrace all suchalterations, modifications and variations that fall within the spiritand scope of the appended claims. Furthermore, to the extent that theterm “includes” is used in either the detailed description or theclaims, such term is intended to be inclusive in a manner similar to theterm “comprising” as “comprising” is interpreted when employed as atransitional word in a claim.

What is claimed is:
 1. A low-flow, fluid conserving shear nozzleassembly, comprising: an insert member having two opposed power nozzlesthat are configured to be in fluid communication with an exit orifice orthroat and an interaction region formed in the insert member, the exitorifice or throat located at an end opposite from where the two opposedpower nozzles meet the interaction region; and a nozzle housingenclosing an interior volume along an inlet axis which receives theinsert member, the nozzle housing including a lateral side wallaperture, wherein the two opposed power nozzles are defined by theinsert member and the nozzle housing and the two opposed power nozzlesare configured to receive pressurized fluid such that the pressurizedfluid flows into the two opposed power nozzles so that a first fluidflow and a second fluid flow are created and are aimed by the twoopposed power nozzles into the interaction region, and wherein thelateral side wall aperture is in communication with the interactionregion of the insert member and wherein the lateral side wall apertureis defined through a sidewall in the nozzle housing for creating,issuing or permitting a uniform spray fan on a plane generallyperpendicular to the inlet axis of said nozzle housing to emanate fromthe lateral side wall aperture.
 2. The shear nozzle assembly of claim 1,wherein the interaction region is substantially rectangular and definedby sidewalls within the insert member wherein the sidewalls projectupwardly from a planar floor surface.
 3. The shear nozzle assembly ofclaim 1, wherein the lateral side wall aperture is aligned along a sprayaxis, wherein the spray axis is generally perpendicular to the inletaxis of the nozzle housing wherein the insert member and the nozzlehousing extend along the inlet axis.
 4. The shear nozzle assembly ofclaim 3, wherein pressurized fluid is introduced to at least one fluidpassage adjacent a distal end of the insert member, where the twoopposed power nozzles and the interaction region are positioned adjacenta proximal end of the insert member such that the distal end andproximal end align along the inlet axis.
 5. The shear nozzle assembly ofclaim 1, wherein the insert member includes sidewall features definingfilter post arrays to filter pressurized fluid passing into and thoughthe interior volume of the housing and into the two opposed powernozzles.
 6. The shear nozzle assembly of claim 1, wherein the insertmember is received within a bottom opening of the nozzle housing andpermits fluid to flow into the interior volume of the nozzle housingaround the insert member.
 7. The shear nozzle assembly of claim 1,wherein the position of the two opposed power nozzles relative to theinteraction region includes a top clearance dimension and a bottomclearance dimension wherein the top clearance dimension is greater thanthe bottom clearance dimension.
 8. The shear nozzle assembly of claim 1,wherein the interaction region of the insert member is defined partiallyby a first sidewall, a second sidewall and a floor surface.
 9. The shearnozzle assembly of claim 8, wherein the first sidewall and secondsidewall are opposite one another and are substantially planar.
 10. Theshear nozzle assembly of claim 1, wherein the nozzle housing includes adome-shaped tip with a diameter size of approximately 5.6 mm.
 11. Theshear nozzle assembly of claim 1, wherein the nozzle assembly issues theuniform spray fan having aim angles between about minus 10 degrees toabout plus 10 degrees from the plane generally perpendicular to theinlet axis of said nozzle housing, with a low flow rate of about 150mL/min to about 300 mL/min at 25 psi, and is capable of reliablyinitiating spraying liquids having a viscosity from about 1 CP up toabout 25 CP.
 12. The shear nozzle assembly of claim 4, wherein the atleast one fluid passage is defined by features located along an outersurface of the insert member and an inner surface of the nozzle housing.13. The shear nozzle assembly of claim 1, wherein the insert memberfurther comprises a first lateral inlet and a second lateral inletformed along an outer surface of the insert member, wherein the firstlateral inlet and the second lateral inlet are in communication with thetwo opposed power nozzles.
 14. A method of assembling a low-flowminiature shear nozzle assembly comprising: providing a nozzle housingenclosing an interior volume along an inlet axis and including anaperture along a sidewall of the nozzle housing; forming an elongatedinsert member having two opposed power nozzles that are in fluidcommunication with an interaction region of the elongated insert member,the interaction region having an exit orifice or exit throat located atan end opposite where the two opposed power nozzles meet the interactionregion; receiving, in the interior volume of the nozzle housing, theinsert member wherein at least one fluid passage is defined by theinsert member and the nozzle housing; and aligning the interactionregion of the insert member with the aperture of the nozzle housingwherein the at least one fluid passage is in fluid communication withsaid two opposed power nozzles that are in fluid communication with theinteraction region for issuing a uniform spray fan on a plane generallyperpendicular to the inlet axis of said nozzle housing to emanate fromthe aperture.
 15. The method of assembling a low-flow miniature shearspray nozzle assembly of claim 14, wherein the step of forming theinsert member further comprises positioning the two opposed powernozzles relative to the interaction region to include a top clearancedimension and a bottom clearance dimension wherein the top clearancedimension is greater than the bottom clearance dimension.